SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c41d2a644063d075925a2420e5b417c98f762cac9be94260715b643ff088ba1b' 
  AND token = '+1WPWB66O6LTtuMcetn4gmupBqDyE9lxFL5EYxHDA2I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}